A Quick Chainmaille History Lesson

Maille was invented some time in the mid 1st millennium BC, but it is unknown where and by whom it was first used. It may have been invented independently in Japan and in Europe. The earliest finds altogether are from 5th Century BC Synthian graves. Etruscan or Celtic examples date to ca. the 3rd century BC.
The Roman Republic first came into contact with maille fighting the Gauls in northern Italy. It so impressed the Romans that the Roman army adopted the technology for their troops.

The use of maille was prominent throughout the High Middle Ages, and reached its apex in the 13th century, when full body suits of maille armour were developed.

In the 14th century, plate armour began to replace maille. It could still be seen after this point being worn by those who could not afford plate, however, and it was also common to wear a shirt of maille beneath plate armour to protect the joints and the groin.

Today, very few examples of ancient mail survive. The vast bulk of maille was broken up, and used as scouring pads through the late Middle Ages.